In a communication network having a plurality of electronic control units connected to a transmission path in order to communicate with each others by sending signals through the transmission path, it is a problem to have a waveform distortion caused by a reflection and/or ringing of the signal.
The technique of Patent Reference 1 is configured to have a ferrite bead as an attenuation element at a node (the connection end of the electronic control unit) of the transmission path in order to eliminate a harmonic noise. It is also well-known to have a circuit element such as L, R, and C instead of a ferrite bead.
The technique of Patent Reference 2 is configured to have a filter comprising a resistor and a coil connected in parallel at a branch connector installed in the transmission path, thereby attenuating a signal component of frequency band in the reflected wave.